20-nm ready for tape out in 2012, says ST

LONDON  STMicroelectronics NV will be ready to tape out designs using a 20-nm CMOS low power process technology in the fourth quarter of 2012, according to Jean-Marc Chery, the company’s chief technology officer.

However, ST is not indicating it will ready to make those designs itself, which raises questions about how long ST can rely on its 300-mm wafer fab in Crolles, near Grenoble, France to be its leading-edge R&D and production site.

Chery was speaking at ST's annual analysts's day held here. The company's executives said the company was aiming at 5 to 7 percent capex to sales ratio as part of the "asset lighter" strategy the company is pursuing. It achieved 5.3 percent in 2009. However, that appears to leave no room for ST to ever lay down the several billions of dollars needed to wholly-own a new leading-edge fab.

Whatever does get taped out in a 20-nm design in 2012 is likely to be manufactured first at GlobalFoundries wafer fab in Dresden, Germany or another foundry that is also in the International Semiconductor Development Alliance (ISDA) based around IBM Microelectronics. It could even be one of the first designs to made at a newly-opened GlobalFoundries fab in New York.

GlobalFoundries is known to be working on a 22-nm process at Dresden which will be used to start operations at the Albany fab that is underconstruction.

"I am very confident we will be able to tape out 20-nm LP in Q4 2012," said Chery. His slide showed that while work on 20-nm is for delivery to ST through an ISDA fab is beginning now in the second quarter of 2010, the same work for delivery through an STMicroelectronics fab is not due to start until Q1 2012.

ST has some processes on its roadmap including general purpose 40-nm and 28-nm that it does not intend to be able to manufacture itself, according to Chery's presentation.

"Beyond 20-nm we will have to change the transistor architecture. Planar will be unable to sustain [suitable operation] below 20-nm." Chery said ST faces a choice between fully depeleted silicon-on-insulator (FD-SOI) and FinFETs. Of course ST will only be a participant in those decisions, which are likely to be taken among the lead manufacturing partners within ISDA.

"Unfortunately you must use double-patterning, which effects productivity." Chery said he expects cost of ownership issues around extreme ultraviolet lithography to be "confirmed" in the third or fourth quarter of this year allowing decisions about a move to EUV lithography to be taken thereafter.